I don't know much about these 6.4s being a 6.0 guy but a friend of mine has had a 6.4 F350 dully for about a year now. Other than a DPF delete and Tune its all stock. The truck has recently developed a problem with shutting off right after you start it. It will start right up and then die in about 1-2 seconds. It will do this about 2-3 times until it stays on or you clear the code (P0506). Any ideas what could be causing this? I was thinking it could be a fuel delivery problem? :dunno: Filters were changed about a 2 months ago with OEM ones.